Architectural fabric is fabric used as a building structure or part of a building structure. It typically provides protection for humans from elements such as wind, sun, and rain. It may be a permanent structure or a temporary one. If temporary, it may be retractable or removable, for example by folding, rolling, or otherwise storing.
There are several requirements for architectural fabric. It must be strong enough to withstand wind and other stresses during assembly and use. It must be flexible and durable, so that it can be folded or rolled and its strength and integrity are maintained over time. It must be UV light resistant. UV light tends to degrade and weaken fabric over time. A fabric that is UV resistant will stand up under this exposure. It should generally be fire retardant and waterproof. It should be easily seamed (or “welded”) and these seams must be strong, both at room temperature and extreme temperatures. It must also be aesthetically pleasing.
A known architectural fabric is a composite consisting of fiberglass fabric coated with PTFE. Although this product has certain desirable qualities, it is not suitably flexible. The fabric thus cannot be used efficiently in applications where convenient removal of the fabric is needed.
Another known architectural fabric has a coating of PVC or acrylic on polyester fabric. These products have flexibility but only limited durability. Unless specially treated, these fabrics are flammable and tend to degrade under UV light. After a certain amount of flexing and UV exposure, these products develop cracks or other imperfections that allow water to penetrate the fabric at the point where it has been compromised.
Another known architectural fabric is that disclosed in U.S. Pat. No. 6,770,577B2 to Kelmartin et al. The article disclosed therein comprises a polytetrafluoroethylene fabric attached to at least one composite membrane of a porous polytetrafluoroethylene film having a fluoropolymer adhesive (such as THV) contained in its pores. The porous polytetrafluoroethylene film is provided to make the article durable and aesthetically pleasing. Addition of the film requires additional processing, however. The film also tends to mute any pigments or colors in the fabric or the THV.
In situations where panels of fabric are welded together at elevated temperatures, seam strength is compromised when using known fabrics. Polymers such as THV may soften at elevated temperatures, thereby compromising seam strength.
An economical, weldable, waterproof, fire retardant architectural fabric with exceptional seam strength is needed in the industry.